Feasibility of improving platelet-rich plasma therapy by using chitosan with high platelet activation ability

Abstract

Platelet-rich plasma (PRP) is blood plasma containing a high number of platelets that release growth factors for wound healing and tissue regeneration. In the present study, the feasibility of improving PRP therapy by using chitosan that exhibits high platelet activation ability was investigated. A total of 13 chitosan samples with different molecular weight (Mw) and degree of deacetylation (DDA) were individually added to blood samples of rats and the amount of growth factors, albumin and fibrinogen in plasma was measured. To examine the influence of plasma activated by chitosan on the proliferation of fibroblasts and adipose tissue-derived stromal cells (ASCs), the plasma was added to the culture medium of human fibroblasts and adipose tissue-derived stromal cells. Chitosan with a DDA of >75% increased the release of platelet factor 4 into the plasma. The amount of growth factors released into the plasma and platelet activation varied depending on the Mw and DDA, while albumin and fibrinogen were hardly affected. The proliferation rate was highest when using plasma activated by chitosan with a DDA of 75-85% and an Mw of 50,000-190,000 Da. These results suggested that the effectiveness of PRP therapy may be improved by using chitosan with a DDA of 75-85% and an Mw of 50,000-190,000 Da.

Keywords: cell proliferation; chitosan; deacetylation; growth factor; platelet activation; platelet-rich plasma.

Figure 1.

Amount of PF4 in plasma. Values are expressed as the mean ± standard deviation (n=4). *P<0.0001, **P<0.001 vs. b. ^#P<0.05 vs. all other samples. Each number corresponds to a chitosan sample defined in Table I. PF4, platelet factor 4; b, blank.

Figure 2.

Amount of (A) PDGF-AB, (B) IGF-1, (C) PDGF-BB and (D) HGF in plasma. Each number corresponds to a chitosan sample defined in Table I. Values are expressed as the mean ± standard deviation (n=4). *P<0.0001, **P<0.0005, ***P<0.001 vs. b. ^#P<0.0005, ^##P<0.05 vs. all other samples. PDGF, platelet-derived growth factor; IGF, insulin growth factor; HGF, hepatocyte growth factor; b, blank.

Figure 3.

Amount of albumin and fibrinogen in plasma. Each number corresponds to a chitosan sample defined in Table I. Values are expressed as the mean ± standard deviation (n=4). b, blank.

Figure 4.

Proliferation of human fibroblasts and ASCs. Each number corresponds to a chitosan sample defined in Table I. Values are expressed as the mean ± standard deviation (n=4). *P<0.0005, **P<0.001 vs. b. ASC, adipose tissue-derived stromal cell; OD, optical density; b, blank.